Bar cage for grinders



M. F. WILLIAMS.

BAR CAGE FOR GRINDERS.

APPLICATION man NOV-25, 921.

1,420,355 Patented June 20, 1922.

warren snares;

Parent OFFICE.

MILTON F. WILLIAMS, OF ST. LOUIS, MISSOURI, ASSIGNOR TO WILLIAMS PATENT CRUSHER & PULVERIZER COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

BAR CAGE FOR GRINDERS.

Application filed November 25, 1921.

T 0 all whom it may concern:

Be it known that I, MILTON F. WILLIAMS, a citizen of the United States, residing at St. Louis, State of Missouri, have invented certain new and useful Improvements in Bar Cages for Grinders, of which the following is a specification.

This invention relates to certain new and useful improvements in bar cages for grinders, the peculiarities of which will be hereinafter fully described and claimed.

The main object of my invention is to provide cage bars having a recess forming a deflecting surface interposed between cut ting edges, and alternating with the discharge opening between adjacent bars, and adapted to deflect inward into the path of rotary hammers the material being reduced; and second, to provide a reversible bar embodying my invention.

In reducing mills that operate on screenings and other feed material such as cotton- 1 seed oil-cake, it is desirable to keep the material in motion at the cutting edges to prevent clogglng the dlscharge openings and tofacilitate the cutting action between the rotary hammers and the cage. In the exemplification of my invention illustrated in the accompanying figure of the drawing, I have shown a bar cage comprising bars A mounted in arcuate sides B concentric with a shaft C supporting hammers or cutters D by hammer rods E and discs F, or other suitable hammer mounts. Any suitable hammers or cutters may be used, but the one shown herewith is especially adapted for grinding feed on account of its radially located cutting edge G traveling in a hammer circle indicated by the arrows in close proximity to the inner face of the bars A.

The inner face of each bar consists of two surfaces H and I lying in planes substantially tangent to the hammer circle indicated by the arrows, and said surfaces are connected by a concave surface J lying in a cylindrical plane the front side of which is alined with the tangent surface I, and the rear side of which forms a surface lying in a radial plane R and intersects the tangent surface H thereby forming a cutting edge K at the rear side of the recess. This cutting edge K is thus interposed between the next succeeding adjacent discharge opening and a primary cutting edge L, formed by Specification of Letters Patent.

Patented June 20, 1922.

Serial No. 517,755.

the intersection of the tangent plane I with the front plane surface M to which it is inclmed in order to form the cutting edge L. The sides of the bar may be parallel to each other as shown at M and M, or they maybe inclined to each other as at M N forming a diminished bar as shown; or otherwise. l/Vith parallel sides M M, the bar may have a similar concave recess with curved surface J interposed between cutting edges L and K, so that the bar may be readily reversed in the cage when the cutof the bar is thus extended by reversing it.

Furthermore, the recess with the curve surface J may be larger than that with the curved surface J on the opposite face, whereby a different action or degree of reduction, depending upon the material operated on, may be obtained. Some material will be better reduced by the fine or smaller recess, while a coarse material is better handled on a larger recess such as J. The inclined surfaces H and I are preferably about 15 degrees with a tangent to the hammer circle to give the desired clearance for the material, and to form the cutting edges K and L with a radial and side surface respectively. The surface I guides the material driven forward by the hammer or cutting face G, while the curved surface J changes its direction and deflects it radially inward over the cutting edge K on which it is further reduced in conjunction with rotary hammers. Two cutting edges are thus formed on the inner face of the bar,- the primary cutting edge L, and the secondary cutting edge K,both extending throughout the length of the bar. The primary cutting edge L at the front face of each bar is directly adjacent to the discharge opening between the bars, while the cutting edge K forming a secondary cutting edge, is near the other side of the bar and the material cut on said edge would be discharged through the following discharge opening as it passes over the adjacent plane surface H.

Thus a concave recess with a deflecting surface J J alternates with a discharge opening, and the discharge is facilitated while the cutting action is more than doubled by the cutting edges and cove recess above described.

The steel of which these cage bars are made is preferably of point 40 carbon so that they may be tempered at the cutting ed es, or otherwise hardened, whereby the e ect of the cutting edges is improved and the life of the bar is extended.

I claim:

1. The combination with rotary hammers, of an arcuate cage comprising bars separated to form discharge openings, and each bar having a recess on its inner face formed by a surface lying in substantially a radial plane through the cage center and intersecting an inner face of the bar forming a cutting edge, and a concave surface connecting said cutting edge and radial surface with a surface that intersects the front side face of said bar and forms a primary cutting edge at the front adjacent discharge opening, said concave forming a deflecting surface adapted to direct the material being reduced on the primary cutting edge into the path of the hammers and in front of said radial plane surface forming a secondary cutting edge for further reduction.

2. The combination with rotary hammers, of an arcuate cage comprising bars separated to form discharge openings, and each bar having a recess on its inner face formed by surfaces lying in planes substantially radial to the hammer circle and tangent to the path of the outer ends of said hammers respectively and forming cutting edges, and by a concave surface connecting said surfaces and adapted to deflect inward in front of the radial face cutting edge the material guided to the recess by said tangential sur ace.

3. The combination with rotary hammers, of an arcuate cage comprising bars separated to form discharge openings, and each bar having its inner face formed by surfaces substantially tangent to the hammer circle, and connected b a concave surface lying in a cylindrical p ane the front side of which is alined with one tangent surface and the rear side intersects the other tangent surface by a plane surface substantially radial to the hammer circle, thereb forming a series of primary and secon ary cutting edges respectively, and forming deflecting recesses alternating with discharge openings, substantially as described.

4. The combination with rotary hammers, of an arcuate cage comprising arcuate sides and reversible bars having concave recesses in opposite faces,said recesses having curved surfaces adapted to deflect the material being reduced into the path of the hammers, substantially as described.

5. In a machine of the character described, an arcuate cage comprising reversible bars consisting of parallel sides forming discharge openings with those of adjacent bars, and of inner and outer faces in each bar inclined to said parallel sides and forming acute and obtuse angles therewith,- both inner and outer faces having a concave deflecting recess forming a cutting edge between said acute and obtuse angles.

6. In a machine of the character described, an arcuate cage comprising side pieces and reversible bars mounted therein, and each having on opposite faces a concave deflecting recess interposed between two cutting edges,the recess on one face being larger than on the opposite face, substantlally as described.

In testimony whereof I have affixed my signature.

MILTON F. WILLIAMS. 

